(I am in a line to pay for my meal at a pay-by-weight salad bar that is self-serve. The customer ahead of me has a small salad and hands the cashier a 20 bill. He receives 19 dollars and loose change back.)

Customer: “Wait, that can’t be right. The salad should be about 4 dollars. Let me weigh that again.”

Cashier: “No! That’s the price. You’re holding up the line.”

(Ignoring him, the customer reaches over and weighs the salad again while the cashier protests. The salad weighs in at about 4 dollars.)

Customer: “See? It should cost more.”

Cashier: “Go. You paid, you’ve got your change, get out!”

Customer:*shrugs*

Me: “Can I get 3 dollars off my salad too?”

Cashier: “What?”

Me: “Yeah, you gave that guy a discount.”

Cashier: “Wait… what?”

(The manager wanders over and I explain what has happened. He turns to the cashier.)